This group of patients will be managed with the no sedation protocol. If agitation occurred, searching for a cause of patient discomfort will be carried out (e.g., tube obstruction or migration, hypoxia, and pain), and managed accordingly. The patient will be reassured and allowed to see his relatives for psychological support if needed, and physical restraints will never be used. If the patient remained agitated, he/she receive IV a bolus of midazolam of 0.5-5 mg as needed to get comfortable and calm. Afterwards, we will start a new trial of management with no sedation; if the sedation has to be repeated three times, we will keep the patient sedated by DIS protocol according to the control group protocol. We will not allow crossover between the groups. We will keep the shifted patients to the DIS protocol after failure of no-sedation protocol in their parent group according to the intention to treat principle.

The patients will be managed by DIS. Richmond agitation and sedation score (RASS) will be used for monitoring the depth of sedation

Ventilator-free days (Number of days from day-1 to day-28) on which the patient did not need assistance to his breathe.